Intake Vacum Leak
 

I just brought my 88 TII to the dealer to have a few things fixed (power windows, chrge AC, ect) and while there had them run a few checks on it.

So they found a vacum leak somehwere on the intake side. They said it was down underneath the intercooler somewhere, and that it was pretty small.

Their advice was to not fix it, as I have alot of miles on my engine (118,000 or so) and that opening everything up to fix a small leak would bring a chance of getting some crud, or small piece of something into the rototrs, which could very easily break an apex seal.

what do you guys think abotu that diagnois? I havne't noticed any problems with how the car is running, but I will be doing some more work on it soon, right now I just have a downpipe and high flow cat, I'll be getting cat back and intake soon. Although with this bit of news it will probably be boost gauge and AF meter first.

thanks for any help, and for making through this long post
(also how do you spell vacum? vacuum? vacume?)

The dealer is full of shit...there is no more chance of crud getting into your engine and breaking an apex seal, now, rather than when the engine was brand new. I'd say take it apart, replace the gaskets, and replace all the vacuum lines with silicon, and that should fix your intake leak. keep in mind this isn't 30 minute job or anything, especially if its your first time. This should probably take you several hours.

leak
 

If your car is running fine.....it will run better if you find that leak. Taking off the intercooler is simple. To prevent anything dropping inside the intakes, just use some rags to cover them up. My idle was screwy when I got my 88. I found a leak on the intake manifold close to the firewall and my idle problem was fixed. It would be a good idea to find that leak for driveability.

silicone hoses
 

How hard is to replace the hoses with silicone ones? Like how much am I going ot haev to take apart? any kind of special tools I would need? ect? any pages that give a good idea of how to go about it?

Re: silicone hoses
 

You'll have to remove the upper intake manifold to do it. You just need a good ratchet set and some wrenches, along with scissors, screwdrivers, and pliers. You'll need to get the silicone hose and some wire ties. Try http://www.hosetechniques.com/ .

Its not too difficult a job, you just need to be careful not to drop anything intake the intake runners. No special tools needed. Just a socket set, and maybe some screwdrivers. You can order the intake gaskets from Mazda. Mazdatrix has silicon vacuum hose. I don't remember offhand how much and what sizes you need, but if you call Mazdatrix and tell them the year and model of your car, they will know. Just make sure you you replace the vacuum hose one at a time and make sure everything goes back together the way it was before. I've never worked on a turbo so I'm guessing there are a lot more vacuum lines than on my NA.